ARMSTRONG WHITWORTH A.W.17 ARIES. Another lesser-known British military prototype of the late 1920s is the Armstrong Whitworth A.W.17 Aries, a two-seat Army Cooperation general-purpose biplane. Fortunately a general arrangement drawing. prepared for the Air Ministry and traced on 15th April 1929. survived the war-time bombing of A.W.A.'s Coventry offices. The only noticeable difference between the drawing and the actual 1929 prototype J9037 is a Townend ring cowling over the 460-h.p. Armstrong Siddeley (special geared) Jaguar IV.Only one prototype was built. Tested in 1930, the Aries Mk. I was virtually a twin of the more successful Type 137 Atlas Mks. I and II which served with the R.A.F.